1.2. Field of the Invention
The invention relates to the field of bulk product transportation and inventory management. More particularly, the invention relates to an application stored on a computer readable medium which, when executed, causes a computer to optimize allocation, transportation routing, transportation vehicle/route scheduling and, preferably, product blending, in the movement of one or more bulk products from supply locations to consumption locations using a heterogeneous fleet of transportation vehicles over a predefined period of time.
1.3. Description of Related Art
Current approaches to optimizing product transportation, whether for the movement of discrete products or bulk products, generally focus on transportation routing and/or vehicle scheduling and do not consider inventory management. In addition, these approaches typically require one or more of the following: a single homogeneous cargo or multiple cargos that cannot be mixed; the use of a homogenous fleet of vessels; travel between a single supply location and a single demand location; and a constant rate of supply and demand. Generally, these approaches also focus on minimizing cost rather than maximizing net profit.
TurboRouter® is a tool recently developed by the Norwegian Marine Technology Research Institute, MARINTEK Logistics. It performs vessel routing and scheduling calculations. The purpose of the tool is to allow a commercial shipping company, as opposed to a chartering party, to maximize the revenue obtained by shipping optional cargo in addition to contract cargos that must be shipped. This tool, however, does not account for inventory management or envision blending.
The shipping of ammonia has been addressed by M. Christiansen et. al., Decomposition of a combined inventory and time constrained ship routing problem, Transportation Science, 33(1): 3-16 (1999). This article poses the problem where inventory management and routing are constrained by time-window requirements and vessels are permitted to carry partial loads. A fleet of vessels transport a single bulk product between production and consumption harbors. The economic calculations of this approach oversimplify real problems and assume constant rates of production and consumption.
The minimum cost inventory routing problem for multiple bulk liquid products (which cannot be mixed) is addressed by D. Ronen, Marine inventory routing: shipments planning, Journal of the Operational Research Society, 53: 108-114 (2002). The vessels in this routing problem have multiple compartments and each vessel is restricted to loading and unloading at only one port. Additionally, this routing problem only allows a homogeneous pool of vessels.
There have been numerous publications in the field of vessel routing and scheduling. One survey article is Ship routing and scheduling: status and perspectives, Transportation Science, 38(1): 1-18, M. Christiansen, K. Fagerholt, and D. Ronen (2004). One overview article is Marine Transportation, Handbooks in Operations Research and Management Science Transportation, M. Christiansen, K. Fagerholt, B. Nygreen, D. Ronen, edited by C. Barnhart and G. Laporte (2007).
One publication of note is Scheduling Ocean Transportation of Crude Oil, Management Science, G. G. Brown, G. W. Graves, D. Ronen, 33(3): 335-346 (1987). This paper addresses a crude oil marine transportation problem. The modeling problem described therein includes the following assumptions/simplifications: (1) each cargo (i.e., crude oil to be shipped) moves between a single loading port and a single discharging port; (2) the cargo shipped must always be a full vessel load (i.e., the cargo must be of a fixed size); and (3) each vessel is the same size. In addition, the objective function of the model is to minimize cost as opposed to net profit margin.
Another publication of note is Fleet management models and algorithms for an oil tanker routing and scheduling problem, H. D. Sherali, S. M. Al-Yakoob, M. M. Hassan, IIE Trans. 31: 395-406 (1999). This paper also addresses a crude oil marine transportation modeling problem. Again, the modeling problem characteristics are such that each voyage must consist of a single loading port and a single discharging port and each cargo must be a full vessel load. In addition, the objective is to minimize cost as opposed to net profit margin. The problem addressed in this paper is different from the preceding paper in that the vessels do not have to be the same size and there is an explicit treatment of vessel compartments.
There is a need in the art for an application that optimizes the total net profit associated with product allocation, transportation routing, and transportation vehicle/route scheduling and, optionally, product blending. There is a need in the art for an application that perform this function in a manner that permits the movement of multiple types and qualities of bulk product, each with non-constant rates of supply (production) and demand (consumption), and each with different monetary values, from one or more supply locations to one or more demand locations, using a heterogeneous fleet of vessels, where each vessel may make multiple loads and discharges. In particular, such an application would provide significant financial benefits in the movement of petroleum and petroleum derived products from supply locations to demand locations.
The aforementioned figures are provided for the purposes of illustration only. The data in the illustrative spreadsheets and user interface screen shots is representative data from a hypothetical, not an actual, problem. Accordingly, the results derived there from, which are set forth in the illustrative user interface screen shots and sample reports are representative results to a hypothetical problem.